Research into pregnancy complications is taken to new heights

14 March 2011

Having placentas delivered from America and studying patients while climbing mountains is all part of the day job for Dr Andrew Murray, who is leading an unusual research project into pregnancy complications funded by West Sussex-based children’s charity Action Medical Research.

Dr Murray, from the University of Cambridge, is working with researchers from the University of Colorado Denver, who are sending him samples of healthy placenta tissue from women who are taking part in the project after giving birth in Leadville, Colorado – a town which sits at 3,100 metres high (over a third the height of Everest).

He is comparing the tissue samples from the women from high altitudes, where oxygen levels are lower, with those of women who gave birth at sea level who either did or didn’t have pregnancy complications.

He says: “There is already quite well established research in pregnancy which shows babies from high altitude mothers are more susceptible to conditions such as pre-eclampsia and fetal growth restriction.

“However, some of these mothers do successfully adapt and we want to learn not only what effect low oxygen has, but also how a normal altitude placenta might adapt to low oxygen as well.”

The nature of the work meant Dr Murray had to develop an innovative new method of pre-treating placenta tissue samples so they can be frozen ready for delivery from the USA, without being damaged or altered.

He said: “This advance means that if a sample is being collected at 3am in Colorado it can be quickly and easily preserved by one of the nursing staff on site and shipped to our lab in Cambridge for analysis.”

The researchers working with Dr Murray aim to increase our understanding of what causes some of the most devastating complications in pregnancy – such as miscarriage, stillbirth, pre-eclampsia and, in particular, fetal growth restriction – that are linked to problems with the placenta.

An unborn baby needs a constant supply of nutrients and oxygen and relies on the placenta to deliver everything from their mothers’ blood. If the placenta isn’t working properly, there can be serious consequences, including miscarriage, pre-eclampsia, stillbirth and fetal growth restriction.

Fetal growth restriction, for example, is a major problem, affecting up to eight per cent of pregnancies.1Babies can grow so dangerously slowly in the womb that they are at risk of death and disability. Estimates suggest over half of unexplained stillbirths are linked to fetal growth restriction.2

Even those babies who are born alive can be so small that they are still at risk of dying. Some develop lifelong disabilities, such as cerebral palsy and learning difficulties. They also have an increased chance of developing heart disease, strokes and diabetes during adulthood.

Around 60,000 babies suffer from fetal growth restriction each year in the UK.3 Around 1,000 die as a result of their condition.3 Currently, there is no way to boost the babies’ growth while they are still in the womb, meaning parents can face a stark choice between risking continuing with the pregnancy and having the baby delivered prematurely.

Dr Murray says: “My background is studying the heart and muscles at high altitude. Some people can climb mountains easily without an oxygen mask. Others suffer major altitude sickness and just can’t do it and feel exhausted at altitude.

“I have conducted studies at the base camp of Everest to see how mitochondria, tiny structures which produce energy for the cell, adapt at altitude in the people who do climb successfully. It is thought the mechanisms that can alter mitochondria function in some people on Everest may be similar to what can happen in the placenta.

“Lack of oxygen or hypoxia is a feature for many serious conditions – critical illness, heart failure, anaemia, lung failure and cystic fibrosis are all associated with having low oxygen levels. It is a well documented issue in the heart and muscles but not in the placenta.

“At the moment, the theory is that it’s a problem with the cells in the placenta itself so perhaps we could use therapies to target these cells. This is a very under-studied area of research.”

Dr Alexandra Dedman, Senior Research Evaluation Manager, said: “The researchers hope their work will eventually lead to new ways to screen for fetal growth restriction and prevent the lasting harm it can cause to babies. They plan to work towards new blood tests, which could allow doctors to identify babies who are struggling in the womb earlier.

They also believe their findings could guide the development of the first-ever treatments for the condition. An effective treatment could save babies’ lives and spare them from long-term disabilities.”

Action Medical Research is the leading UK-wide medical research charity dedicated to helping babies and children. We know that medical research can save and change children’s lives. For nearly 60 years we have been instrumental in significant medical breakthroughs, including the development of the UK polio vaccine and ultrasound scanning in pregnancy. Today, we continue to find and fund the very best medical research to help stop the suffering of babies and children caused by disease and disability. We want to make a difference in:

•tackling premature birth and treating sick and vulnerable babies

•helping children affected by disability, disabling conditions and infections

•targeting rare diseases that together severely affect many forgotten children.